<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            width: 100px;
            height: 100px;
            background-color: pink;
        }
    </style>
</head>
<body>
<script>
    window.addEventListener('load',function () {
        var div = document.querySelector('div');
        window.addEventListener('resize',function () {
            console.log(window.innerWidth);
            console.log('变化了');
            if (window.innerWidth <= 600){
                div.style.display = 'none';
            }else {
                div.style.display = 'block';
            }
        })
    })
</script>
<div></div>
</body>
</html>